The Biggs Bunch are at it again! This time Cameron, Carsen, and Brynlee find themselves in a real life pirate tale. The Time Pirate they are trying to stop is after the Lost Treasure of Lima. Things get tricky when all four time travelers are captured by the real pirates who originally stole the treasure from the Spanish. From there, our heroes are in a race against time. The mystery of the treasure includes the death of almost every member of the pirate crew of the "Mary Dear," which now includes them! Can they escape the doomed fate of the crew?